[7.01] Photometry of Three Fields in the Orion Nebula Cluster.

We have initiated a program of repeated R and I photometry of three fields in the Orion Nebula Cluster. Our observations were performed at the Lowell Observatory 31-inch telescope which, under an agreement with Northern Arizona University and the NURO Consortium, is operated 60% of the time as the National
Undergraduate Research Observatory. These three fields and several others
covering the entire cluster have been studied by Herbst and his coworkers (Choi and
Herbst, 1996, AJ, 111, 283; Eaton et al., 1995, AJ, 110, 1735; Herbst et al.,
1994, AJ, 108,1906; Edwards et al., 1993, ApJ, 106, 372; Mandel and Herbst, 1991,
ApJ, 383, L75; Attridge and Herbst, 1992, ApJ, 398, L61) who carried out
Cousins I photometry, observing each field once per night over several seasons. They
have found that each field contains many T-Tauri like variable stars. Choi and
Herbst (1996, AJ, 111, 283) have proposed that a variety of mechanisms are
responsible for these variations. By obtaining color information and higher t
ime resolution, we hope to shed further light on the nature of these
stars. We provide a preliminary report on this project.

The author(s) of this abstract have provided an email address for comments about the abstract: mcfarlan@dickinson.edu